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21.
A method to study the proliferation of human brain tumors, is presented. Non radioactive 5-Iododeoxyuridine (2.4 gr) infused over a 24 hours period is detected in situ on histologic section by an immunological technique (peroxidase-anti-peroxidase) using a specific anti-Iododeoxyuridine antibody. This exploration utilised in 45 patients is easy, reliable and harmless. All cells which enter in S phase of cellular cycle during the infusion are labelled. So the cellular kinetics of all the brain tumor cells (malignant cells, inflammatory stroma reaction cells, reactive astrocytes, endothelial and muscular cells of the vessels) are detected on the same histological section, as well as all the others proliferative cells of the body (leukocytes, primitive tumor of the metastatic brain localisation...) if multiples biopsies are done. 8 of 9 gliomas of low histological malignancy (grade I and II) have a slow cellular kinetic. The 23 astrocytomas of different histological malignancy (grade III and IV) have variable proliferative speed (7 very fast, 8 fast and 8 slow). Only the large cells of the pinealoma are very proliferative, the lymphoid stroma is quiescent. The 5 metastasis have a slow to very fast kinetic without correlation with the cellular differentiation except in one case (important differentiation and slow cellular proliferation). The 5 lymphoma cells kinetics are well correlated with the histologic differentiation (3 large cells poor differentiated lymphomas and very fast kinetic, 2 better differentiated and slower proliferation). The 2 meningiomas proliferate slowly. The biochemical and histopathological grounds of the presented method and the limits of quantification are discussed. This method is compared with this using Bromodeoxyuridine. The correlation between proliferation and histologic malignancy is analysed. The use of cytokinetic results for therapeutic and prognosis need further statistical anatomoclinical studies. 相似文献
22.
Concurrent Validation of Substance Abusers Self-Reports Against Collateral Information: Percentage Agreement VS. k Vs. Yule's Y 总被引:1,自引:0,他引:1
Norman G. Hoffmann Fred G. Ninonuevo 《Alcoholism, clinical and experimental research》1994,18(2):231-237
The ability for chemical users to give an accurate self-report of (ubrbnce use vs. abstinence has been questioned. This study hatlgated its concurrent validity, against collateral ratings. The results indicated that validity of reports of chemical use must be evaluated in the context of the validity of other types of information. Chemical use items were corroborated about as often as such nonchemical use items as reports of emergency room visits, arrests, md hospitalizations, thus arguing against the presence of a specific denlal syndrome or overarching tendency toward self-misrepresenletion. Relative concurrent validities seemed more a function of such factors as item salience and specificity. No consistent trend in patient over-or underreporting of chemical use was found. The choice of concurrent validation statistic is important and can influence interpretation of results. Current standards such as percentage agreement and K were seen as flawed; comparisons of results based on these two measures, as well as Yule's Y led to the conclusion that Yule's Y is the statistic of choice. 相似文献
23.
24.
H. Dienemann C. Trainer H. Hoffmann H. Bülzebruck T. Muley K. Kayser I. Vogt-Moykopf 《Der Chirurg》1997,68(10):1014-1019
Zusammenfassung. Nach Lungenresektion und ipsilateraler Lymphknotendissektion wegen Bronchialcarcinoms verblieb in 88 von 2464 F?llen (3,6
%) mikroskopisch Residualtumor (R1) am zentralen Bronchusresektionsrand. Sieben Patienten entwickelten eine Insuffizienz der
Bronchusnaht, 2 weitere eine Nachblutung bzw. eine Herzluxation (Morbidit?t 8,0 %). Die Hospitalletalit?t betrug 16,6 %. Todesursachen
waren Bronchusnahtinsuffizienz (n = 7), Arrosionsblutung (n = 4), respiratorische Insuffizienz (n = 1) und Pleuraempyem (n = 1). Eine postoperative Bestrahlung wurde bei 43 Patienten durchgeführt. Die mediane überlebenszeit aller Patienten nach
R1-Resektion war 16 Monate gegenüber 37 Monaten nach R0-Resektion (p < 0,001). Die überlebenszeit war unabh?ngig von Tumorstadium und -histologie, Lokalisation des Residualtumors in der Bronchuswand
und einer Nachbestrahlung. Inkomplette Resektionen sind durch intraoperativen Schnellschnitt zu verifizieren. Sofern funktionell
vertretbar, sollte in den Stadien I und II eine Nachresektion (R0) angestrebt werden; auch in den Stadien III a und III b
ist bei R0-Resektion ein statistisch signifikanter überlebensvorteil gegenüber R1-Resektion zu verzeichnen, jedoch weniger
deutlich als in niedrigeren Stadien.
相似文献
25.
S Bauer I Wolff N Werner P Hoffmann R Herzschuh K Oemus F W Rath R Voigt 《Toxicology and industrial health》1992,8(3):141-156
In dry etching processes--one of the sources of potential exposure to toxic wastes in the semiconductor industry--complex mixtures of inorganic and organic compounds arise from reactions between feed stock gases (BCl3/Cl2), top layers (aluminium photoresist), and the carrier gas (N2). Two different fractions of the complex mixture--one an ethanolic solution (ES) and the other an insoluble liquid residue (LR)--were examined for acute oral toxicity in rats. Analytical data showed that the ethanol soluble fraction contained mainly inorganic compounds, whereas the residue contained various halogenated hydrocarbons. Neither death nor behavioral changes occurred after oral administration and observation up to 23 days. ES caused a lower mean arterial blood pressure in both sexes, increased P-R-intervals in male rats, and caused some mild biochemical and hematological alterations and changes in relative organ weights compared to the control groups. Exposure to LR influenced food and water intake, and caused a significant decrease in body weights, signs of polyurie, as well as changes in various relative organ weights and biochemical and hematological parameters. The blood pressure of the male animals fell and the heart rates of both sexes decreased. 相似文献
26.
In premature neonates a patent ductus arteriosus causes often other complications thus the immediate closure of the patent ductus arteriosus should be preferred or recommended. Performing the surgical closure of the ductus within the incubator can avoid complications during transportation from the premature neonates intensive care unit to the operating room. 25 very small premature neonates or those with another burden in addition were operated upon in the incubator on the premature infants intensive care unit of our hospital during the period from January 1987 to April 1989. No complications occurred during the operation, especially not caused by the strange circumstances for the operating team. Wound infections because of possible bacterial contamination of the incubator or the room were not observed during the postoperative period. 相似文献
27.
Dr. Flemming Moesgaard M.D. Mogens Lykkegaard Nielsen M.D. Ph.D. Allan Hjortrup M.D. Peter Kjersgaard M.D. Carsten Sørensen M.D. Peter Nørgaard Larsen M.D. Steen Hoffmann M.D. 《Diseases of the colon and rectum》1989,32(1):36-38
One hundred ninety patients with peritonitis at the time of abdominal surgery were allocated at random to systemic antibiotic
treatment alone or systemic antibiotic treatment combined with topical application of antibiotics in the wound at the time
of wound closure. The overall wound infection rate was 17 percent without significant difference between the two treatment
groups (P>0.80). 相似文献
28.
B M Taute B Zipprich G Hoffmann W Saul 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1988,43(21):624-627
It is reported on the very rare occurrence of a benign tumor in common hepatic bile duct of a 33-year-old woman, associated with obstructive jaundice. Clinical diagnosis and treatment are described, histological typing like fibroblastic tumor with neurogenic parts are discussed and a short review of the literature is given. 相似文献
29.
David F Kroon M Louise Lawson Craig S Derkay Karen Hoffmann Joe McCook 《Otolaryngology--head and neck surgery》2002,126(5):499-504
OBJECTIVE: The study goal was to demonstrate the prevalence and severity of external auditory exostoses (EAEs) in a population of surfers and to examine the relationship between these lesions and the length of time surfed as well as water temperature in which the swimmers surfed. It was hypothesized that subjects who predominantly surfed in colder waters had more frequent and more severe exostoses. METHODS: Two hundred two avid surfers (91% male and 9% female, median age 17 years) were included in the study. EAEs were graded based on the extent of external auditory canal patency; grades of normal (100% patency), mild (66% to 99% patency), and moderate-severe (<66% patency) were assigned. Otoscopic findings were correlated with data collected via questionnaires that detailed surfing habits. RESULTS: There was a 38% overall prevalence of EAEs, with 69% of lesions graded as mild and 31% graded as moderate-severe. Professional surfers (odds ratio 3.8) and those subjects who surfed predominantly in colder waters (odds ratio 5.8) were found to be at a significantly increased risk for the development of EAEs. The number of years surfed was also found to be significant, increasing one's risk for developing an exostosis by 12% per year and for developing more severe lesions by 10% per year. Individuals who had moderate-severe EAEs were significantly more likely to be willing to surf in colder waters than were those who had mild EAEs (odds ratio 4.3). CONCLUSIONS: EAEs are more prevalent in cold water surfers, and additional years surfing increase one's risk not only for developing an EAE but also for developing more severe lesions. 相似文献
30.
M. Sand T. Gambichler G. Moussa F. G. Bechara D. Sand P. Altmeyer K. Hoffmann 《Skin research and technology》2006,12(2):114-118
BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary. 相似文献